1. Field of the Invention
The invention relates to a bearing bush having at least one internal annular groove at at least one bush end for accommodating a sealing ring, and a method of producing such a bearing bush.
2. Description of Related Art
Bearing bushes have many uses, e.g. in door hinges, as roller bearing systems, pedal and clutch bearings etc. On the inside, the bearing bush may be coated with a bearing material which exhibits good sliding characteristics and low wear.
However, sliding and wear characteristics may be impaired by the penetration of foreign material into the bearing. Dirt, moisture and particles abraded from adjacent components have a direct effect on the bearing function of the bush, such that the latter may have to be replaced after only a short service life if no special precautions are taken.
In addition, in the case of lubricated bearing bushes the lubricant may escape from the bush, which also causes the sliding characteristics to deteriorate over time.
To remedy this, bushes have already been developed which comprise a groove milled in at one or both ends, into which groove a specially shaped, in general stepped sealing ring is inserted to prevent the penetration of dirt and the like into the bearing. The disadvantage of such bushes is that a certain minimum thickness must be available to enable such a sealing member accommodating groove to be milled in. This process is complex and expensive. Grooves produced by milling also have a rectangular cross section, such that specially shaped sealing rings are required to fit in the milled grooves.